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Biventricular heart failure remains a major challenge and total artificial heart (TAH) (SynCardia Systems Inc., Tucson, AZ, USA) bear hurdles, in particular in long-term application. Ventricular membrane rupture of a TAH is a feared complication and often implies a fatal outcome. Hereby we present the first case of successful and effective replacement of a TAH right ventricle due to the membrane rupture.

Cardiac tamponade after ventricular assist device or total artificial heart implantation can typically occur within days or weeks after surgery. This report describes the case of a woman who presented over 4 years after SynCardia 70cc total artificial heart implantation, with physiology consistent with right ventricular outflow tract obstruction. The cause was initially attributed to device membrane failure based on the device console waveform; however, during operative exploration, a large amount of proteinaceous exudate was surrounding the device and causing the obstruction. This report illustrates how tamponade can result years after device implantation, secondary to porosity of the outflow grafts.

A 30-year-old patient had angiosarcoma of the right atrium with a negative outcome. The use of a SynCardia or Carmat was not possible due to invasion of the right atrium by the tumor, so we implanted two HeartWare ventricular assist devices (Medtronic, Minneapolis, MN) in a total artificial heart configuration using a technique not previously described. The surgical follow-up was simple, and the patient remained alive 30 days postoperatively. The technique we describe herein offers new prospects for the implantation of two HeartWare ventricular assist devices in a total artificial heart configuration.

Background Circulatory failure necessitating cardiac transplantation will ultimately develop in many patients with functional single-ventricle physiology. Interest in the use of mechanical circulatory support (MCS) in this population is growing. Methods This was a retrospective case series of patients with functional single-ventricle physiology who underwent MCS with a ventricular assist device or a total artificial heart as a bridge to cardiac transplantation between January 2006 and December 2014. Baseline demographics, intraoperative data, postoperative complications, and outcome data were collected from the medical record. Results MCS was used in 5 patients: HeartWare ventricular assist device (HeartWare International, Framingham, MA) in 1 patient, SynCardia total artificial heart (SynCardia Systems, Tucson, AZ) in 1, Thoratec Paracorporeal ventricular assist device (Thoratec Corp, Pleasanton, CA) in 1, and the Berlin Heart EXCOR (Berlin Heart Inc, The Woodlands, TX) in 2. The mean age at MCS was 12 ± 8 years. There were 2 early deaths at 12 and 28 days after MCS: 1 patient died of multiorgan system failure and 1 of neurologic injury. Overall, neurologic complications occurred in 3 patients (60%), and 1 patient (20%) required renal replacement therapy. Three patients (60%) underwent successful cardiac transplantation. The median time on the waiting list was 59 days (interquartile range, 18 to 126 days), and the median duration of MCS was 60 days (interquartile range, 28 to 93 days). At the time of transplant, all 3 patients were ambulatory, without the need for mechanical ventilation, and end-organ dysfunction had resolved. The 3 patients who received transplants were discharged from the hospital and were alive at an average follow-up of 9 ± 14 months. Conclusions MCS can be successfully used as a bridge to transplantation in patients with a failing single-ventricle circulation. Use of MCS can allow for resolution of end-organ dysfunction and rehabilitation, leading to improved outcomes in this difficult population.

We present a case report illustrating a novel method of placing a total artificial heart in a small child.

An infant unable to be weaned from cardiopulmonary bypass after orthotopic heart transplantation was cannulated for extracorporeal membrane oxygenation. During the next 3 days, allograft failure and intracardiac thrombosis necessitated cardiectomy. To provide acute mechanical circulatory support, artificial atrial chambers were constructed with Gore-Tex conduits and PediMag centrifugal pumps were connected to each by Berlin Heart EXCOR cannulae. The PediMag pumps were subsequently exchanged for 10-mL Berlin Heart EXCOR pumps. After 60 days of support by total artificial heart, the patient was bridged successfully to a second heart transplant.

Symptomatic cardiac tumors can lead to a rapid clinical deterioration and death. Prompt surgical resection is ideal in this situation as it is the only proven treatment to date. We report the radical resection of a large malignant cardiac tumor that obstructed the right ventricular outflow tract. Extensive resection precluded reconstruction and limited the ability to implant a total artificial heart; thus, 2 paracorporeal devices were implanted instead.

The 50-cc SynCardia total artificial heart is designed to facilitate orthotopic replacement of the native ventricles in patients with a body surface area below 1.7 m(2) in need of long-term circulatory support as a result of end-stage biventricular heart failure. We describe the implementation of this technology in a female patient with irreversible cardiogenic shock on the grounds of acute myocardial infarction and chronic ischemic cardiomyopathy.

With implantable cardiac assist devices increasingly proving their effectiveness as therapeutic options for end-stage heart failure, it is important for clinicians to understand the unique physiology of device-assisted circulation. Preload sensitivity as it relates to cardiac assist devices is derived from the Frank-Starling relationship between human ventricular filling pressures and ventricular stroke volume. In this review, we stratify the preload sensitivity of 17 implantable cardiac assist devices relative to the native heart and discuss the effect of preload sensitivity on left ventricular volume unloading, levels of cardiac support, and the future development of continuous-flow total artificial heart technology.

Background Combined heart-liver transplantation (CHLT) has been utilized as a life-saving procedure in those with end-stage cardiac and hepatic pathology. Techniques and outcomes of this procedure are varied. We sought to review the Cleveland Clinic experience with CHLT. Methods This study is a retrospective chart review of patients who received simultaneous heart and liver transplantation between January 2006 and December 2012. Results Five patients received CHLT. The mean age was 49 (± 20) years. All cardiac pathology was nonischemic cardiomyopathy, with a mean ejection fraction of 0.36 (± 0.13). Three of the 5 were on preoperative inotropic support, 1 of which required placement of a total artificial heart for support pretransplant. Liver pathology was amyloid in 1 patient and hepatitis C in the remaining 4. Mean Model for End-Stage Liver Disease score was 17 (± 5), and mean Childs-Pugh score was 8 (± 1). Survival, now at a mean of 38 (± 20) months remains 100%, with no cardiac or hepatic graft dysfunction or episodes of rejection. One hospital readmission was required for gastroenteritis at 15 months posttransplant. Conclusions These results suggest that excellent outcomes can be achieved in this extremely sick cohort of patients, and add to the growing literature of perioperative management of CHLT recipients.

Background The mortality rate of patients experiencing acute myocardial infarction (AMI) complicated by cardiogenic shock remains high. After conventional therapies have failed, ventricular assist devices (VADs) have been used to bridge patients to recovery or transplantation. Methods A voluntary US registry was established to track all patients implanted with the AB5000 VAD. We report the results of the first 100 patients in the registry with the indication of AMI cardiogenic shock. Data were retrospectively reviewed for demographics, preimplant condition, surgical techniques, and outcomes. Survival was assessed at 30 days after VAD explant or at discharge. Myocardial recovery (subset of survival) was defined as satisfactory unassisted native cardiac function for 30 days after VAD explant or at discharge. Results Forty patients (40%) survived to 30 days after VAD explant or discharge of the first 100 patients. Of the survivors, 63% (n = 25) experienced myocardial recovery. Patients who recovered required an average of 25 ± 22 days of VAD support. The estimated survival after explant for the recovery patients at 2 years after VAD explant was 78%. Conclusions Results from this nationwide registry suggest that VADs can restore normal hemodynamics and support recovery of native cardiac function in the majority of survivors when conventional therapies fail. However, a longer duration of support than previously recognized may be required. In the absence of clinical guidelines, early aggressive use of VAD support in AMI complicated by cardiogenic shock may improve outcomes, and recovery of native cardiac function should always be the primary goal.

End-stage heart failure is a growing problem associated with a high mortality using conventional medical care. Although cardiac transplantation is an excellent treatment option, it is a limited resource and most patients are ineligible for cardiac transplantation using standard listing criteria. Increasingly, newer surgical options for these patients include the usage of marginal donor organs in an extended criteria-alternate list heart transplant program (EC-AL), or left ventricular assist devices as destination therapy (DT-LVAD). The purpose of this study was to compare baseline characteristics and outcomes after EC-AL versus DT-LVAD.From March 2000 to August 2008, 153 consecutive patients who had been turned down for standard heart transplantation underwent either EC-AL or DT-LVAD. The most common reasons for standard heart transplant ineligibility for both groups were advanced age, diabetes mellitus with end-organ dysfunction, and significant renal insufficiency. Patients in the alternate list program received a donor organ that had been turned down by all other centers for standard list recipients. The most common reasons for donor heart refusal were decreased left ventricular function, left ventricle hypertrophy, or coronary artery disease. Outcomes for both groups were retrospectively reviewed after Institutional Review Board permission was obtained. Comparisons were also made between patients that had been matched by propensity score analysis.In all, 93 patients underwent EC-AL, and 60 underwent DT-LVAD. Baseline preoperative characteristics of both groups were similar except that 87% of DT-LVAD patients (52 of 60) required preoperative mechanical or inotropic support whereas only 51% of EC-AL patients (47 of 93) required support (p0.0001). Thirty-day operative mortality and 1-year survival were 2.5% and 82.2% for EC-AL and 6.7% and 77.5% DT-LVAD, respectively (p=0.2411 and p=0.5036). Overall survival at 3 years was better for EC-AL versus DT-LVAD. The DT-LVAD patients had improved survival compared with the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) trial DT-LVAD cohort, a historical control. These findings were corroborated in the analysis of propensity-matched patients.Preoperatively, the DT-LVAD cohort was more unstable, with greater need for inotropes or mechanical support. Despite this, perioperative and 1-year mortality was similar for the two groups. Three-year survival was better for EC-AL. The DT-LVAD patient survival was better than that of the REMATCH DT-LVAD cohort.

Background Bridge to heart transplantation with a left ventricular assist device (LVAD) can be a promising therapy for patients who are not effectively stabilized with conservative measures. However, referral for LVAD therapy may be limited secondary to reports of poor outcomes when mechanical circulatory support is required before transplantation. Methods A retrospective review was undertaken to evaluate outcomes in United Network of Organ Sharing (UNOS) status 1 heart transplant recipients who were bridged to transplant with an implantable LVAD or with intravenous inotropes only from 1994 to 2007. Preoperative characteristics, posttransplant survival, and postoperative complications were compared between 86 patients with an implantable LVAD and 173 patients bridged with intravenous inotropes only. Results The patients had similar baseline characteristics and pretransplant hemodynamics. Hemodynamics in the LVAD group, as measured by cardiac index, pulmonary vascular resistance, central venous pressure, and pulmonary capillary wedge pressure, significantly improved during mechanical support. Short-term and long-term posttransplant survival and the incidence of posttransplant infectious complications and rejection episodes during the first year was similar. The incidence of posttransplant renal dysfunction was higher in patients bridged with inotropes. Conclusions Patients bridged to transplant with a LVAD represent a subset of UNOS status 1 patients who deteriorated on intravenous inotropic therapy. Bridging to heart transplantation with an implantable LVAD provides comparable outcomes to similar status 1 patients who were stabilized on inotropic infusions only. In contrast with International Society of Heart and Lung Transplantation data, no increase in posttransplant morbidity or mortality occurred in LVAD-bridged patients.

Background When implanted in patients with biventricular failure, the CardioWest total artificial heart has asserted itself over time as a reliable bridge-to-transplant device that as yet is used by only a few international teams. The aim of this single-center retrospective study is to assess both the comorbidity and survival of patients awaiting heart transplants while receiving circulatory support with a CardioWest total artificial heart. Methods From 1990 to December 2006, 42 patients received a CardioWest total artificial heart at our center. Mean age at the time of implantation was 45.7 ± 9.5 years, and 40 patients (95%) were men. Idiopathic or dilated cardiomyopathy was diagnosed in 45.2% (n = 19) of the patients and ischemic cardiomyopathy in 42.8% (n = 18). Average body surface area was 1.9 ± 0.22 m 2 . Results Duration of support was 1 to 292 days (mean, 101 ± 86 days). Twelve patients died (28.5%) while receiving device support, and 30 patients (71.5%) underwent transplantation. Actuarial survival rates for the transplanted patients were 90% (n = 25), 81% (n = 14), and 76% (n = 10) at 1, 5, and 10 years, respectively. Causes of death during device support included multiorgan failure in 6 (50%), sepsis in 2, acute respiratory distress syndrome in 2, alveolar hemorrhage in 1, and other cause in 1. There were no device malfunctions that led to patient death. Adverse events included stroke in 3 patients (7%) and infections in 35 patients (85%) during support. Conclusions The CardioWest total artificial heart is an excellent bridge-to-transplant device for patients with biventricular failure. Our study demonstrates excellent safety, reliability, and efficiency. Exceptional outcome after transplantation underlines its capacity to aid in end-organ recovery.

Background. Safety and efficacy studies of various mechanical circulatory support devices are important, but may not be strictly comparable. Lacking prospective randomized studies for different devices, we believe that comparison of risk factor analyses may give the surgeon a tool more powerful than current studies for matching a patient with an appropriate device. In this paper, we report risk factor profiles for bridge to transplantation with the CardioWest total artificial heart and summarize reports for other devices. Methods. A multiinstitutional risk factor analysis of the CardioWest total artificial heart, as a bridge to transplantation in 81 patients, was conducted. Univariate analyses were performed on 43 preimplantation prognostic factors. From this group, eight factors were chosen for multivariate analysis. Our results were compared with all recent risk factor analyses for other devices. Results. Independent predictors for death at three intervals by multivariate analysis were as follows: “implant to transplant”: history of smoking (odds ratio, 34); “implant to 30 days after transplant”: history of smoking (odds ratio, 10.00), prothrombin time greater than 16 seconds (odds ratio, 4.76); and “implant to 1 year after transplant”: prothrombin time greater than 16 seconds (odds ratio, 3.85). The major difference between this experience and multiple reported experiences with left ventricular assist devices is that for left ventricular assist devices, but not for the temporary CardioWest total artificial heart, right heart failure, high central venous pressure, and being on a ventilator (with or without sepsis) were independent predictors of mortality. Conclusions. Risk factors for bridge to transplantation with the CardioWest total artificial heart are different from those reported for left ventricular assist devices. Recognition of these risk factor differences may facilitate appropriate device selection. (Ann Thorac Surg 2008;85:1639 ‐ 45) © 2008 by The Society of Thoracic Surgeons

Background Most patients undergoing destination therapy with a HeartMate XVE left ventricular assist device will eventually require pump exchange to continue long-term cardiac support. Methods To determine whether left ventricular assist device exchange can be accomplished with low morbidity and mortality, we retrospectively reviewed the records of 14 patients who experienced pump malfunction and subsequently required replacement of their HeartMate XVE left ventricular assist devices with HeartMate II axial-flow pumps. We collected data regarding duration of support and reasons for pump failure, perioperative characteristics, and operative approach. Results On average, patients were supported 473 ± 233 days with HeartMate XVE pumps. Seven early patients required both subcostal and sternotomy incisions; 7 later patients had subcostal incisions only. Thirteen patients underwent successful exchange to the HeartMate II; 1 patient died in the operating room. Another patient died in the perioperative period (30-day mortality, 14% [2 of 14]). There were significant differences between the two groups. The patients who required only subcostal incisions had shorter operative times (187 versus 220 minutes; p = 0.04) and required fewer transfused blood products (packed red blood cells, 8.6 versus 28.7 units; p = 0.03; and fresh-frozen plasma, 12.4 versus 30.9 units; p = 0.04). Additionally, the patients with subcostal incisions had shorter postoperative intensive care unit stays (5.3 ± 1.1 versus 8.4 ± 3.1 days for redo sternotomy patients; p = 0.03). Of the survivors, average hospital stay was 22 ± 14 days. Average long-term follow-up was 11.2 ± 7.8 months; 71% (10 of 14) of patients are currently alive. Conclusions Exchange of a HeartMate XVE to a HeartMate II can be accomplished with relatively low morbidity and mortality through a subcostal approach.

The presence of heparin-induced thrombocytopenia (HIT) increases the risk for thromboembolic events in ventricular assist device (VAD) patients undergoing transplantation. However, cardiopulmonary bypass with alternative anticoagulants is often complicated by bleeding. Owing to this concern, we compared outcomes of HIT-positive versus control bridge-to-transplantation VAD patients; both groups were reexposed to heparin for cardiopulmonary bypass during transplant.From February 2000 to January 2006, data were reviewed on 92 consecutive adult patients who underwent VAD placement as a bridge to transplantation. Patients in whom thrombocytopenia developed after heparin exposure were tested for HIT with an enzyme-linked immunosorbent assay for antiheparin/platelet factor-4 (HPF4) antibody (GTI Diagnostics, Waukesha, Wisconsin). During VAD support, heparin was avoided in HIT-positive patients, but all patients were reexposed to heparin during transplantation. Comparisons between HIT-positive and control patients for survival and freedom from thromboembolic events were determined using the Kaplan-Meier method and log-rank test. Continuous and categorical variables were compared using the Wilcoxon rank-sum and Student t test.Twenty-four of the 92 patients (26.1%) were determined to be HIT positive by enzyme-linked immunosorbent assay. Survival to transplant was not different between the two groups. When compared with control patients, HIT-positive patients who were reexposed to heparin had a greater decrease in platelet counts immediately after transplant (postoperative days 1 to 4, p0.05). Despite this transient thrombocytopenia, there was no difference in posttransplant mortality or thromboembolism.Heparin-induced thrombocytopenia-positive VAD patients did not experience increased thromboembolism or mortality after heparin reexposure. In light of the risks of using heparin alternatives, heparin reexposure is a safe management strategy for HIT-positive VAD patients.

A successful left ventricular assist device (LVAD) long-term support in an outpatient setting demands that device-related complications are reduced to a minimum. We hypothesized that late onset driveline infections have serious implications on the anticipated application of LVAD as permanent therapy.Between 1996 and 2005, 73 patients were implanted with the Novacor (World Heart Corp, Ottawa, Ontario, Canada; n = 35) or the HeartMate (Thoratec Corp, Pleasanton, CA; n = 38) as either bridge to transplantation (n = 44) or destination therapy (n = 29). Our analysis focused on patients with late-onset infection (or = 30 days) of the driveline exit site with prior clinical healing of all incisions.Late driveline infections developed in 17 patients (23%) at a median of 158 days (intraquartile range [IQR]: 68 to 213 days) after implantation. The median duration of support in this subgroup was 400 days (IQR, 283 to 849 days). Despite an aggressive treatment algorithm, repeat surgical revision was needed in 12 patients, up to six times in 2 individuals. In 6 patients, the infection progressed to pump pocket infections that led to urgent heart transplantation (n = 4) or explantation (n = 2). The individual risk that a driveline infection would develop dramatically increased with the duration of support, reaching 94% at 1 year. Multivariate analysis identified duration of support (p0.001) and documented trauma at the driveline exit site (p0.001) as independent predictors of infection. Number and duration of readmissions to the hospital significantly increased (p0.001), and long-term follow-up for survival (4.4 +/- 2.2 years, 100% complete) showed a trend towards impaired outcome after driveline infection (5-year survival: 41% versus 70%, p = 0.10).Long-term LVAD support in the current series was jeopardized by late-onset driveline infections, which occurred in all patients with support duration longer than 1 year. Once driveline infections developed, they were difficult to control and significantly increased morbidity.

Severe pulmonary hypertension refractory to medical treatment is a contraindication to orthotopic heart transplantation in most centers. We report our experience in treating severe pulmonary hypertension with mechanical left ventricular unloading using implantable nonpulsatile left ventricular assist devices (LVAD) with continuous flow properties.In ten patients with severe pulmonary hypertension, refractory to medical treatment, an implantable nonpulsatile LVAD was placed for continuous mechanical left ventricular support. Pulmonary hemodynamics were assessed by right heart catheterization prior to and during LVAD implantation, and after orthotopic heart transplantation.The mean (+/-SD) interval of nonpulsatile support was 182 (+/-118) days. Pulmonary artery pressure (mean +/- SD) significantly decreased from 42 +/- 13 to 24 +/- 5 mm Hg (p0.005), the transpulmonary gradient (mean +/- SD) decreased from 20 +/- 6 to 11 +/-5 mm Hg (p0.005), and the pulmonary vascular resistance (mean +/- SD) from 4.8 +/- 1.8 to 2.2 +/- 0.8 Wood units (p0.005) during an interval of one to six months of LVAD support. No significant increases in pulmonary artery pressure, transpulmonary gradient, and pulmonary vascular resistance were observed during an interval of three to six months after orthotopic heart transplantation.This study supports that LVAD support and continuous nonpulsatile mechanical unloading of the left ventricle can reverse medically unresponsive pulmonary hypertension and render patients eligible for orthotopic heart transplantation.

Background Biventricular support before orthotopic heart transplantation (OHT) has been shown to adversely affect short- and long-term outcomes, but the comparative effect of support type is largely unknown. This study determined the comparative effect of univentricular and biventricular support on survival in bridged patients after OHT. Methods The United Network of Organ Sharing database was queried for adult patients bridged to OHT with a univentricular (left ventricular assist device [LVAD]), biventricular (biventricular assist device [BiVAD]), or total artificial heart ([TAH]) device between 2004 and 2012. Unconditional and conditional survivals were compared with the Kaplan-Meier method. Cox proportional hazards regression models were constructed to determine the risk-adjusted influence of support type on death. Results Of the 4,177 patients identified, 3,457 (20.4%), 575 (3.4%), and 145 (0.9%) were bridged with an LVAD, BiVAD, and TAH, respectively. Unadjusted 30-day, 1-year, and 5-year estimated survival was greater in LVAD patients than in the BiVAD and TAH cohorts. After risk-adjustment, BiVAD and TAH were associated with an increased risk of death at all time points. Unadjusted and adjusted 5-year survival, conditional on 1-year survival, was worse, however, in only TAH patients. Conclusions Patients with biventricular failure bridged to OHT with a TAH or BiVAD experience worse short- and long-term survival comparison with those with an LVAD. This difference is most likely due to an increase in early death and depends on the type of BiVAD device implanted.

Background Left ventricular assist devices (LVADs) with continuous flow properties are increasingly used to bridge heart failure patients to cardiac transplantation. Advantages in comparison with the pulsatile LVADs are smaller size, better endurance, and lower thromboembolic events. However, whether these new pumps have similar pre- and posttransplant outcomes is not clear. Methods Fifty patients with a continuous flow device (Micromed DeBakey, Houston, TX or InCor BerlinHeart, Berlin, Germany) were compared with an age-, disease-, and LVAD duration-matched control group (n = 80) supported with a pulsatile device (Novacor, WorldHeart, Oakland, CA or HeartMate, Thoratec Corp, Pleasanton, CA). Results Age (44.3 ± 13.4 vs 46.1 ± 11.1 years), disease (idiopathic dilated cardiomyopathy, 58% vs 65%), and LVAD duration (138 ± 131 vs 128 ± 106 days) were comparable in both groups. Successful bridging to transplantation was similar with continuous flow in comparison with pulsatile device support (52% vs 56%, p = not significant [NS]). Thirty-day mortality after cardiac transplantation in patients with continuous flow LVAD support was 21.7% vs 22.2% with pulsatile LVADs ( p = NS). Reasons for death were similar among the different LVAD groups. Long-term survival was similar in both LVAD groups compared with patients without previous LVAD support. Interestingly, severe rejections were significantly more frequent in patients with a continuous flow LVAD ( p Conclusions The new generation of cardiac assist devices with continuous flow pattern has a similar rate of pre- and posttransplant mortality in comparison with pulsatile LVADs. However, the rate and severity of posttransplant rejection was significantly higher in the group with continuous flow devices. Further studies are warranted to explain the higher rate of severe rejections.

The HeartMate XVE left ventricular assist device is a valuable treatment option for patients with end-stage heart failure. During the past several years, the XVE has undergone a series of design enhancements to improve reliability. We compared the reliability of the two most recent design iterations of the XVE pump (stitch modification to the inflow valve assembly and new inflow valve housing redesign) to the earlier VE version.A retrospective evaluation of device reliability was performed for 268 devices implanted in 245 patients (VE: n = 167 devices, 147 patients, implant dates October 16, 1998, to December 19, 2003; XVE: n = 101 devices, 98 patients, implant dates August 1, 2002, to April 14, 2004).Median duration of device support for the VE and XVE was 159 days (range, 0 to 1,206 days) and 229 days (range, 0 to 693 days), respectively (p = 0.495). Significantly fewer major device malfunctions occurred within the XVE group as compared with the VE group (6 versus 36, respectively; p = 0.0003). The number of major device malfunctions per patient-year of support for inflow valve dysfunction, bearing wear, and other failures for the VE and XVE were 0.2 versus 0.04 (p = 0.006), 0.16 versus 0.01 (p = 0.005), and 0.06 versus 0.04 (p = 1.000), respectively. The freedom from major device malfunction at 1 year was 76% +/- 6% for the VE and 97% +/- 2% for the XVE device (p0.001). The freedom from death as a result of major device malfunction at 1 year was 97% +/- 2% for the VE and 98% +/- 2% for the XVE (p = 0.698).Design enhancements to the HeartMate XVE have significantly reduced the incidence of major device malfunctions compared with the earlier VE model because of a reduction in failure modes from bearing wear and inlet valve dysfunction. Further follow-up is necessary to establish the long-term durability of the most recent XVE pump version.

Background The use of left ventricular assist devices is associated with human leukocyte antigen (HLA) allosensitization. We investigated whether prophylactic treatment with low-dose intravenous immunoglobulin (IVIG), analogous to the use of IgG anti-D (anti-Rh) in preventing Rh immunization, can abrogate HLA allosensitization after left ventricular assist device implantation. Methods We retrospectively reviewed the data from 84 consecutive heart failure patients who underwent implantation of a left ventricular assist device as a bridge to transplantation. After implantation, panel reactive antibody (PRA) was measured biweekly to assess sensitization (defined by PRA > 10%). Patients who were sensitized before left ventricular assist device implantation were excluded from further analysis (n = 12). Patients who either did not require perioperatively transfusions of cellular blood products or received other immunomodifying regimens were also excluded from further analysis (n = 21). The rest of the patients were divided into two groups based on whether they received IVIG, 10 g daily for 3 days (IVIG group, n=26; non-IVIG group, n=25). The decision as to whether patients received IVIG was not randomized but was based on surgeon preference. Results The sensitization rates (expressed as ratio of sensitized patients to total patients at risk) in the two groups were similar at consecutive time points (2, 4, 6, 8, 12, 20 weeks) after left ventricular assist device implantation. Also, mean PRA at the same time points did not differ between the two groups. Overall, 34.6% (9 of 26) of the IVIG group became sensitized during mechanical support, compared with 32% (8 of 25) of the non-IVIG group (p = 1.0). A PRA of 90% or greater (high-degree sensitization) occurred in 15.3% (4 of 26) of the IVIG group and 12.0% (3 of 25) of the non-IVIG group ( p = 0.5). Conclusions The use of low-dose prophylactic IVIG after left ventricular assist device implantation affects neither the incidence nor the severity of HLA allosensitization.

Background Pediatric size pneumatically driven extracorporeal ventricular assist devices (VAD) for infants and small children were introduced into clinical routine in 1992. In the initial period, the results in infants were poor. Since then, several improvements have been introduced with regard to the cannulas, connectors, heparin coating of the blood pump inner surface, anticoagulant treatment and coagulation monitoring, and earlier decision-making in favor of pump implantation before irreversible shock has set in. Methods Since 1990 and as of January 1, 2005, 62 Berlin Heart Excor systems have been implanted in patients below 18 years of age at our institution. The patients were divided into two groups according to the period of treatment: period 1, devices implanted between 1990 and 1998 (n = 34), and period 2, devices implanted between 1999 and 2004 (n = 28). We compared our experience during the earlier and later periods. Results There were no significant differences in the preoperative patient data between the two periods except for time of support (17.9 ± 27.7 days versus 53.2 ± 83.9 days, p = 0.001). In period 1, more patients needed a biventricular VAD whereas in period 2, more patients were effectively treated with a left VAD ( p = 0.05). In the later period, the chest could be primarily closed in a significantly higher percentage of infants (0% versus 89%, p = 0.012), and more infants could be extubated on the VAD (0% versus 55%, p = 0.16). Discharge from the hospital after either weaning from the system or heart transplantation was achieved for 35% in period 1 and for 68% in period 2 ( p = 0.029). Whereas in period 1 there were no survivors in the group of children younger than 1 year old, during period 2, survival in this age group was similar to that of the two groups of older children ( p = 0.024). There was a significant improvement in the discharge rate in period 2 in patients with cardiomyopathy (43% versus 76%, p = 0.045) and postcardiotomy heart failure (0% versus 57%, p = 0.01). Conclusions Earlier implantation of VADs, heparin coating of the blood pumps, and substantial modifications in cannula design, anticoagulation, and the coagulation monitoring regimen have led to a significant increase in the survival and discharge rate, especially among children under 1 year of age. The pediatric size Berlin Heart Excor VAD is a valuable option as a bridge to heart transplantation or recovery for children suffering from cardiogenic shock.

New left ventricular assist devices promise fewer adverse events but, currently, only minor improvements in survival. Small (survival) treatment effects, limited patient populations, and the increasing number of left ventricular assist devices in development challenge the efficient conduct of premarketing trials (especially in destination therapy) and, maybe more importantly, hamper innovation. Novel trial designs would facilitate this process. Among a range of trial designs, we opt for small randomized trials, which would preserve the advantages of randomization and also allow for a shorter enrollment period. We also advocate an evidence shift toward postmarketing studies, with the Interagency Registry of Mechanically Assisted Circulatory Support providing a robust infrastructure.

Poor renal function may affect outcomes after left ventricular assist device (LVAD) placement. Conversely, LVADs may optimize circulation and improve renal function.To assess the relationship between renal function and LVAD use, changes in creatinine clearances (CrCl, in mL/min) were assessed retrospectively in 220 patients who underwent LVAD placement. These patients were also divided into four groups based on CrCl quartiles (47, 48-68, 69-95, and95) and compared for outcomes post-LVAD placement.Eighty-four patients died on LVAD support. Survival on LVAD was worse for patients with the worst baseline CrCl (42%, 52%, 63%, and 79% for 6 month and 26%, 34%, 47%, and 66% for 12 month survival for quartiles 1-4; both p0.01 for trend). Adjusting for other covariates, patients in the lowest CrCl quartile were at a higher risk of dying postimplant (odds ratio 1.95, 95% confidence interval 1.14-3.63). Paired sample analysis showed the following changes in CrCl: preoperative to week 1, 77.0 +/- 46.6 to 92.1 +/- 51.1 (p0.01; n = 202), week 1 to 2, 89.4 +/- 49.2 to 95.2 +/- 52.4 (p = 0.01, n = 171), week 2 to 3, 107.5 +/- 58.1 to 113.7 +/- 66.1 (p = 0.16, n = 74), and week 3 to 4, 111.1 +/- 56.6 to 110.5 +/- 56.8 (p = 0.87, n = 60). For the 60 patients with baseline CrCl less than 50, CrCl increased from 36.7 +/- 9.2 to 60.1 +/- 35.5 (p0.01; n = 55 pairs) from preimplant to week 1. In 37 of these patients (62%) on intraaortic balloon pump support preimplant, CrCl increased from 38.4 +/- 8.2 to 67.9 +/- 40.3 mL/minute (p0.01) during week 1 postimplant. Recovery of renal function to CrCl greater than 50 was associated with a trend towards better 30-day survival (84% vs 66%, p = 0.09).Baseline poor renal function is associated with worse outcomes after LVAD implantation. However, renal function improves substantially and rapidly in post-LVAD survivors and is associated with improved outcomes. These data underscore the importance of careful patient selection for LVAD therapy.

Increased use of continuous-flow left ventricular assist devices (LVADs) to treat advanced heart failure has heightened concern for right ventricular failure after LVAD implantation, which is associated with increased morbidity and mortality. Biventricular support is required in up to 30% of LVAD recipients. Currently, no durable long-term right ventricular assist device (RVAD) has been approved other than the Syncardia (Tucson, AZ) total artificial heart. A recent publication reported the placement of continuous flow LVAD in the heavily trabeculated right ventricle; however, this orientation may jeopardize both assist device and right ventricle function. We describe three cases of right-sided mechanical circulatory support with durable RVAD implanted in the right atrium, allowing long-term support with fewer anatomic limitations as compared with right ventricular cannulation.

Background Previous reports, all concerning pulsatile devices, have indicated an increased risk of development of circulating antileukocyte antigen (HLA; human leukocyte antigen) antibodies during ventricular assist device (VAD) support. We investigated sensitization in patients implanted with the DeBakey VAD (MicroMed Technology, Inc, Houston, TX) axial flow pump as a bridge to heart transplantation. Methods Inclusion criteria for this prospective study were the following. Patients implanted with the DeBakey VAD axial flow pump, without HLA antibodies prior to implantation, with a duration of support of at least one month. The HLA antibody testing for IgG and IgM class I and II antibodies was performed weekly during support, using both a complement dependant cytotoxicity assay and an enzyme-linked immunosorbent assay (ELISA). Retrospective cross match was performed for all patients transplanted. The occurrence of graft rejection was determined by regular endomyocardial biopsies after heart transplantation, graded according to the International Society for Heart and Lung Transplantation (ISHLT) guidelines. Additionally, the transfusion history was reviewed for all patients. Results Fourteen patients were included representing 1,220 cumulative patient-days of support (mean duration time on support, 87 days). No patient developed detectable IgG antibodies to class I or II. One patient had a positive ELISA, corresponding to nonsignificant (6/30) class I IgM antibodies at 3 weeks postimplantation. Ten patients underwent successful heart transplantation, representing 156 cumulative months. No retrospective cross match was positive. The percentage of significant acute rejection episodes (ISHLT grade 3A or more) was 6% and 4.3% in the first 6 months and from 6 to 12 months, respectively. No vascular rejection was noted. The posttransplantation survival rate was 87% at 6 months and 75% at 1 year, respectively. Conclusions Patients implanted with the DeBakey VAD axial flow pump as a bridge to heart transplantation do not appear to be exposed to an increased risk of sensitization.

Background Left ventricular assist device (LVAD) failure and malfunction rates are critical gauges for establishing LVADs as a long-term therapy for end-stage heart failure patients. These device performance measures, however, have been inadequately characterized in the bridge-to-transplantation literature. Methods REMATCH is a randomized trial that compares optimal medical management with LVAD implantation for patients with end-stage heart failure. An independent committee adjudicated patient outcomes. The primary endpoint—survival—was analyzed by intention to treat using the log-rank statistic. Frequency of event occurrence was analyzed by Poisson regression. The time to first event was analyzed by the product limit method. Device performance was disaggregated into confirmed malfunctions and system failures. The latter were events in which patients could not be rescued with backup circulatory support measures. Results The 1-year survival rate was 52% (95% confidence limit [CL]; 40%–63%) for LVAD patients versus 28% (95% CL; 17%–39%) for medical patients and the 2-year survival rate was 29% (95% CL; 19%–40%) for LVAD patients versus 13% (95% CL; 5%–22%) for medical patients. System failure was 0.13 per patient per year and the confirmed LVAD malfunction rate was 0.90. Freedom from device replacement was 87% at 1 year and 37% at 2 years. Conclusions Despite the observed rates of device malfunction and replacement, LVAD implantation confers clinically significant improvement with regard to survival as compared with medical management. Device modifications and innovations for infection management exhibit great promise of improving device performance in the near future.

Background Acute right ventricular failure after heart transplantation is a life-threatening condition, and sometimes the use of mechanical circulatory support is inevitable. The aim of this retrospective study was to investigate the effectiveness of two different mechanical circulatory support systems for this indication. Methods From 1984 to 2003, 28 heart transplant recipients exhibited right ventricular failure resistant to drug therapy. Right ventricular assist device (n = 15) or extracorporeal membrane oxygenation (n = 13) was implanted to support the failing heart. Results Overall in-hospital survival was 43%. In the right ventricular assist device group, only 2 patients (13%) could be weaned from mechanical circulatory support compared with 10 patients (77%) in the extracorporeal membrane oxygenation group ( p = 0.001). Retransplantation was necessary in 6 patients in the right ventricular assist device group and in 1 patient in the extracorporeal membrane oxygenation group ( p = 0.049). There was no difference in patient survival between groups, but graft survival was significantly better in the extracorporeal membrane oxygenation group ( p = 0.005). Conclusions In view of these results, extracorporeal membrane oxygenation seems to be the better option as mechanical circulatory support for right ventricular failure in heart transplantation.

Background The HeartMate vented electric left ventricular assist device has been approved for use as destination therapy. Thus, the study of quality-of-life outcomes, as well as morbidity and mortality, is imperative. The purpose of our study was to describe change with time (from 1 month to 1 year) in patients who received a HeartMate vented electric left ventricular assist device as a bridge to heart transplantation and to identify quality-of-life predictors of survival after left ventricular assist device implantation. Methods A nonrandom sample of 78 patients who received a HeartMate vented electric left ventricular assist device (primarily middle-aged, white married males) who had quality-of-life data at 1, 2, 3, 6, 9, or 12 months after implant was the subject of this report. The sample size decreased with time primarily because of heart transplantation. Patients completed the following booklets of questionnaires: Quality of Life Index, Rating Question Form, Heart Failure Symptom Checklist, and Sickness Impact Profile. Analyses included both descriptive analyses and modeling procedures (mixed-effects models and Cox proportional hazards models). Results Quality-of-life outcomes were fairly good and stable from 1 month to 1 year after HeartMate vented electric left ventricular assist device implantation. Both positive and negative changes were detected in all quality-of-life domains (physical and occupational function, social interaction, somatic sensation, and psychological state) after left ventricular assist device insertion. Items from the physical domain of quality of life, specifically walking and dressing oneself, were significantly associated with the risk of dying after left ventricular assist device implantation. Conclusions Identifying poor quality-of-life outcomes within 1 year after left ventricular assist device implantation provides direction to develop strategies to improve outcomes. Physical and occupational rehabilitation, psychosocial intervention, and monitoring symptom distress and physical disability may contribute to improved quality-of-life outcomes and survival after left ventricular assist device implantation.

Bridging to transplant with a left ventricular assist device (LVAD) can be limited by severe right ventricular failure (RVF). The focus of this study was to ascertain whether early implantation (24 hours) of a right ventricular assist device (RVAD) in patients with severe RVF improved survival and whether severe RVF adversely affected post-transplant survival.We conducted a 10-year review of our bridge to transplant experience using the Heartmate device (Thoratec, Pleasanton, CA, USA), studying patients who required an Abiomed RVAD (Abiomed, Danvers, MA, USA).There were 243 patients who underwent LVAD implantation, of which 17 (7.0%) required an RVAD. Ten patients underwent early RVAD insertion (24 hours) while 7 underwent delayed insertion (24 hours). Bridging to transplant was successful in 11 (64.7%) RVAD patients versus 163 (72.1%) non-RVAD patients (p = 0.046). Of the 10 patients who underwent early RVAD insertion, 7 (70.0%) were successfully bridged. Of the 7 patients who underwent delayed RVAD insertion, 4 (57.1%) were successfully bridged (p0.001). There was no significant difference in post-transplant 1, 5, and 10-year survival between RVAD and non-RVAD patients (71.4%, 71.4%, and 71.4% for RVAD patients, vs 90.5%, 80.4%, and 78.5%, respectively, for non-RVAD patients; p = 0.366). Pretransplant RVAD support was not a risk factor for post-transplant mortality (p = 0.864).Severe RVF adversely impacted bridging to transplant, although survival was improved with early RVAD insertion. The trend toward worse post-transplant survival in the RVAD cohort raises the possibility that if additional patients were evaluated, a difference in survival might be observed, suggesting the need for a multicenter analysis.

The use of left ventricular assist devices (LVADs) is established as a bridge to heart transplantation.All Swedish patients on the waiting list for heart transplantation, treated with LVAD since 1993 were retrospectively collected into a database and analyzed in regards to risk factors for mortality and morbidity.Fifty-nine patients (46 men) with a median age of 49 years (range, 14 to 69 years), Higgins score median of 9 (range, 3 to 15), EuroScore median of 10 (range, 5 to 17) were investigated. Dominating diagnoses were dilated cardiomyopathy in 61% (n = 36) and ischemic cardiomyopathy in 18.6% (n = 11). The patients were supported with LVAD for a median time of 99.5 days (range, 1 to 873 days). Forty-five (76%) patients received transplants, and 3 (5.1%) patients were weaned from the device. Eleven patients (18.6%) died during LVAD treatment. Risk factor analysis for mortality before heart transplantation showed significance for a high total amount of autologous blood transfusions (p0.001), days on mechanical ventilation postoperatively (p0.001), prolonged postoperative intensive care unit stay (p = 0.007), and high central venous pressure 24 hours postoperatively and at the final measurement (p = 0.03 and 0.01, respectively). Mortality with LVAD treatment was 18.6% (n = 11). High C-reactive protein (p = 0.001), low mean arterial pressure (p = 0.03), and high cardiac index (p = 0.03) preoperatively were risk factors for development of right ventricular failure during LVAD treatment.The Swedish experience with LVAD as a bridge to heart transplantation was retrospectively collected into a database. This included data from transplant and nontransplant centers. Figures of mortality and morbidity in the database were comparable to international experience. Specific risk factors were difficult to define retrospectively as a result of different protocols for follow-up among participating centers.

The AbioCor implantable replacement heart (IRH) is the first available totally implantable artificial heart. We recently initiated a multicenter trial of this device in patients with severe, irreversible biventricular failure. Patients who were not candidates for other therapies, including transplantation, were evaluated. All candidates were adults with inotrope-dependent biventricular failure, whose 30-day predicted mortality was higher than 70%. A three-dimensional computerized fit study predicted fit of the AbioCor thoracic unit in all recipients. At operation, the internal battery controller and transcutaneous energy transfer unit were placed. The AbioCor thoracic unit was placed in an orthotopic position after incision of the ventricals. There were 2 intraoperative deaths (due to intraoperative bleeding or aprotinin reaction). Four late deaths were recorded, 1 from multi-system organ failure and 3 cerebrovascular accidents. Autopsy revealed thrombus on the atrial struts of the 3 patients with cerebrovascular accident. Blood pumps and valves were clean on all patients. Significant morbidity was observed, primarily related to preexisting severity of illness. However, 3 patients recovered to the point of being able to take multiple trips outside of the hospital. Two patients were discharged from the hospital, with 1 patient being discharged home for more than 7 months. No significant device malfunctions or multi-system organ failure device-related infections were noted. The AbioCor IRH may be effective therapy for patients with end-stage heart failure. Many milestones have been achieved in the initial trial in humans, including the successful discharge of a patient to home and no significant device malfunctions. The occurrence of stroke is likely related to the presence of thrombus on the atrial struts and may be decreased as these atrial struts have been removed for future clinical implants.

Background Pulsatile left ventricular assist devices are used with increasing frequency to bridge patients with end-stage heart failure to heart transplantation (HTx). Implantation of pulsatile devices is a cumbersome surgical procedure that is associated with major complications, such as bleeding, thromboembolism, and infection. Recently, a continuous axial flow left ventricular assist device (DeBakey ventricular assist device) has been introduced with the goal of reducing the incidence of major complications. Methods We reviewed our experience with 11 patients who received a DeBakey ventricular assist device axial flow pump for bridge to HTx from April 2000 through November 2001. Results Two patients (18.2%) died of multiple-organ failure while on left ventricular assist device support. Bleeding requiring thoracotomy occurred in 2 patients (18.2%). One patient had a minor neurologic event, and one patient developed left ventricular assist device thrombosis, which was successfully treated without pump exchange. Renal failure developed in 1 patient and hepatic dysfunction in 2 patients. There were no instances of right heart failure. No device, pocket, or drive-line infections occurred. Nine patients (9 of 11, 81.8%) had HTx within 51 ± 49 days (range, 11 to 141 days) after left ventricular assist device implant. One patient died 29 days after HTx because of acute rejection. Conclusions The continuous axial flow DeBakey ventricular assist device had reliable features, including a high rate of bridge to HTx. This device had low complication and system failure rates. We consider the DeBakey ventricular assist device a favorable alternative to pulsatile heart assist devices as a bridge to HTx.

Background Right ventricular assist devices (RVADs) have been proposed to improve exposure of the coronary arteries in off-pump surgery. In this study we investigated the impact of the A-Med RVAD on inflammatory response and organ function in patients undergoing coronary artery bypass grafting. Methods Sixty patients were prospectively randomized to conventional surgery with cardiopulmonary bypass (CPB) and cardioplegic arrest, beating heart surgery (off-pump), or beating heart surgery with the RVAD. Serial blood samples were collected postoperatively, for analysis of inflammatory markers, troponin I, protein S100, and free hemoglobin. Renal tubular function was assessed by measuring urine N -acetyl-glucosaminidase activity. Results No hospital deaths or major postoperative complications occurred in the study population. Interleukin-6, interleukin-8, C3a, and troponin I levels after surgery were significantly higher in the CPB group compared with the off-pump and RVAD groups. Free hemoglobin levels immediately after the operation, peak and total S100 levels, and N -acetyl-glucosaminidase activity were also significantly higher in the CPB group. Conclusions Off-pump coronary revascularization, with or without RVAD, reduces inflammatory response, myocardial, neurologic, and renal injury, and decreases hemolysis when compared with conventional surgery with CPB and cardioplegic arrest.

Background . This study evaluates a modification of an ambulatory intraaortic balloon pump (IABP) technique used in patients with heart failure of ischemic origin for bridge to transplant. Methods . In this retrospective review we evaluated the ability to place the ambulatory IABP, any complications, time on device, and success in bridging to transplant on the ambulatory IABP device. In addition, the cost as compared to current ventricular assist devices was determined. Results . Between July 2000 and November 2001, 4 patients have been managed with ambulatory IABP in our combined University of Wisconsin and William S. Middleton Veterans Administration programs. All 4 patients had ischemia as their mode of heart failure, and each had a relative contraindication to standard ventricular assist device use. All 4 patients had ambulatory IABPs successfully placed through the left axillary artery without complication, and were able to ambulate early after ambulatory IABP placement, and increased their rehabilitation status before transplantation. Ambulatory IABP support ranged from 12 to 70 days. All 4 patients have been successfully transplanted and discharged from the hospital. Use of the ambulatory IABP support, even with multiple replacements, translated to 10- to 50-fold savings for each of the reported patients versus standard ventricular assist device use. Conclusions . As a result of our initial experience, we believe that ambulatory IABP is an excellent mode of support in selected patients, and is cost-effective, as compared to conventional ventricular assist device therapy.

Background . Initiating outpatient therapy with ventricular assist devices (VAD) was important in the progress of mechanical circulatory support. This article reviews our experience with VAD therapy from the start of our outpatient program until the present. Methods . Medical records of patients who received a Thoratec para-corporeal VAD, HeartMate vented electrical VAD, or HeartMate pneumatic VAD between 12/1/97 and 9/1/01 were reviewed. Variables included age, type of devices, total duration of VAD support, discharge status, duration of outpatient support, outcome (transplanted, died on support, ongoing), in-hospital length of stay after transplantation, and complications during VAD support. Results . There were 53 device implants in 46 patients. The cumulative patient-days of VAD support was 7,468 (mean duration of support, 138 ± 195 days; median, 95 days; range, 2 to 948 days). Twenty of the 46 patients were discharged with a VAD. The cumulative outpatient days was 3,600 (mean outpatient duration, 157 ± 164 days; median, 83 days; maximum, 560 days). Of the 20 outpatients, 11 received cardiac transplantation, 5 died, and 4 are ongoing as of 9/1/01. Major complications that occurred in the outpatient setting included 5 deaths after hospital readmission (1 sepsis, 1 conduit tear, 3 neurologic events); 4 device infections (3 sepsis, 1 pouch infection); and 3 device malfunctions that required reoperation for pump replacement (1 HeartMate pneumatic and 2 HeartMate vented electrical). No deaths occurred in an outpatient setting. Conclusions . Ventricular assist devices effectively support outpatients for months to years. The anticipated time for postoperative recovery and VAD training before discharge is approximately 14 to 21 days, although shorter times may be possible in the future. Establishing a successful outpatient VAD program is a crucial step toward VAD as definitive therapy for end-stage heart disease.

The Jarvik 2000 Heart is a silent compact axial flow impeller pump which is now undergoing clinical trials for both bridge to transplantation and permanent mechanical circulatory support. The pump is implanted into the apex of the failing left ventricle by left thoracotomy. A vascular graft offloads to the descending thoracic aorta so that only the left pleural cavity is opened. Power supply is through an abdominal drive line or post-auricular titanium pedestal according to the treatment strategy.

We performed a totally endoscopic resection of a left ventricular myxoma using the Heart Port Endoclamp System and conventional endoscopic instruments in a young male patient. It is a feasible and safe procedure with good clinical results and an excellent cosmetic outcome.

Background . Mechanical circulatory assist industries have developed ventricular assist devices (VAD) for short-, intermediate-, and long-term use. The purpose of this report is to describe the progress made with the ABIOMED Biventricular System (BVS) 5000 (ABIOMED, Inc, Danvers, MA) short-term VAD. Methods . From June 1994 through August 2000, all cardiogenic shock patients who required short-term mechanical assist were supported with the ABIOMED BVS 5000. Insertion criteria included any condition that may potentially result in cardiac recovery. A formal algorithm for timing of insertion was established to standardize implantation criteria. Results . A total of 45 patients were supported at Hahnemann University Hospital, Philadelphia, PA. There were 26 male and 19 female patients, with a mean age of 57.9 years (range 33 to 80 years). Devices were inserted for postcardiotomy shock in 36 patients (80%) and precardiotomy shock in 9 patients (20%). The average duration of support was 8.3 days (range 1 to 31 days). Overall, there were 22 (49%) patients weaned from support and 14 (31%) discharged from the hospital. For patients in whom the device was implanted in accordance with an established protocol (group A), the wean and discharge rates were 60% and 43%, respectively. The most common morbidities included bleeding and adverse neurologic events. Conclusions . The ABIOMED BVS 5000 VAD continues to be a valuable form of short-term mechanical assist for acute cardiogenic shock. The formation of a uniform VAD insertion algorithm has helped to standardize protocols in management.

Background . A variety of sophisticated devices have been developed for mechanical circulatory support in patients bridged to cardiac transplantation. Based on 13 years' experience, we have developed specific protocols for patient selection and management for different devices. Methods . The principal systems applied in the bridge-to-transplant cohort are the Thoratec ventricular assist device (n = 144, mean duration of support 53 ± 57 days), the Novacor left ventricular assist system (LVAS) (n = 85, mean duration of support 154 ± 15 days), and the HeartMate LVAS (n = 54, mean duration of support 143 ± 142 days). The Thoratec device is used for biventricular assistance or if the duration of support is expected to be less than 6 months. For long-term support, either the Novacor or HeartMate LVAS are preferred. Results . Despite careful postoperative patient management, this group of patients is prone to a variety of complications. Bleeding occurred in 22% to 35%, right heart failure in 15% to 26%, neurologic disorders in 7% to 28%, infection in 7% to 30%, and liver failure in 11% to 20% of patients. Complications varied with the device applied and the patient's preoperative condition. A total of 73 patients were discharged from hospital for a mean period of 184 days; this cumulative experience amounted to 37.5 patient-years. Conclusions . The Novacor and the HeartMate systems offer the additional possibility of discharging patients during support if they fulfill certain criteria. The main reasons for rehospitalization were thromboembolic and infectious complications.

Background . Patients with end-stage heart failure placed on a cardiac assist device show at least some degree of improvement of cardiac function. In a subgroup of selected patients, some hearts recovered considerable function. In these patients the device was removed and cardiac transplantation was no longer necessary. We report our long-term experience with these weaned patients. Methods . As of today, 512 cardiac assist devices of various types (Berlin Heart, Berlin, Germany; Novacor, World Heart, Ottawa, Ontario, Canada; TCI, ThermoCardio Systems, Inc, Woburn, MA; DeBakey, Micromed Technology Inc, Houston, TX) were implanted in patients with end-stage heart failure in our institution. Of these, 95 patients belonged to a subgroup of patients with nonischemic, idiopathic, dilated cardiomyopathy who were implanted with a left ventricular support system (Novacor 84, TCI 10, Berlin Heart 1) between 1994 and 2000. All were routinely examined by echocardiography for improvement of cardiac function. The left ventricular diameter in diastole (LVIDd) and left ventricular ejection fraction (LVEF) served as the main parameters to assess changes in cardiac performance. Under the conditions of a running device, an LVIDd below 60 mm and an LVEF above 40% were the criteria to do further echocardiographic studies when the pump was turned off for up to 20 minutes. Results . Twenty-eight patients (26 men, 2 women; ages 18 to 64 yrs; history of heart failure, 1 to 17 yrs) fulfilled the criteria of improved cardiac performance and were weaned from the device. Since then, 16 patients have continued "normal" heart function with follow-up times ranging from 1 month to 5.5 years (group B). Three patients died of noncardiac causes (group C). Eight patients were transplanted from 1 to 17 months later and one died on the waiting list (group A). Statistically significant differences between groups A and B were calculated for the duration of heart failure (9 versus 2 years, p = 0.0002). Differences in LVIDd before removal of the device (57 versus 51 mm, p = 0.0420), LVEF after 2 months of unloading (30 versus 49%, p = 0.0300), and LVEF preexplantation (43 versus 52%, p = 0.0001) were significant. Overall, 17% of the cohort of 95 patients were weaned successfully. Conclusions . Weaning from cardiac assist devices is feasible for selected patients; it saves donor hearts and is preferred to cardiac transplantation. However, as of today no reliable parameter predicts outcome after weaning and none determines the possibility of device removal before implantation in advance.

Advances in technology and increased clinical need have led to the development of a new type of blood pump. The Jarvik 2000 Heart is an electrically powered, axial-flow left ventricular assist device that has been developed during the past 13 years. Unlike first-generation left ventricular assist devices, which were developed in the 1970s and were designed to totally capture the cardiac output, the Jarvik 2000 is designed to normalize the cardiac output by augmenting the function of the chronically failed heart for extended periods. Design iterations have been tested in 67 animals, and clinical trials have recently begun. Three patients have received the Jarvik 2000 as a bridge to transplantation, and 1 patient is being supported permanently outside the hospital. All 4 patients have improved from New York Heart Association functional class IV to class I, and 2 of them have been discharged from the hospital after heart transplantation. The experimental and clinical results indicate that the Jarvik 2000 can provide physiologic support with minimal complications and is reliable, biocompatible, and easy to implant.

Background . With increasing use of left ventricular assist devices (LVAD) worldwide, the economics of LVAD implantation have become an important focus of concern. Although these devices have high unit costs, they are the only hope for survival for a large group of terminally ill patients and are likely to have an expansion in indications for use. Methods . We calculated the costs associated with long-term LVAD implantation. We used the ratio of cost-to-charges method to calculate hospital costs per resource category, market prices for drugs and device, and payments for physician services. Results . Based on our experience with "bridge-to-transplantation" patients, we estimated average first-year costs to be $222,460 including professional fees and $192,154 excluding professional fees. The latter figure is comparable to average first-year costs for cardiac transplantation, which is $176,605 without professional fees at our institution. Conclusions . The costs of LVAD therapy will change after the first year of implantation, and device reliability and longevity will be important factors in determining these costs. Should the costs of LVAD therapy continue to track those of cardiac transplantation, devices will be cost-effective only if they offer similar efficacy to cardiac transplantation.

The Novacor Left Ventricular Assist System (LVAS) (Novacor Corp, Oakland, CA) was initially console-based and has been available since 1993 in a wearable configuration. It has been successfully used for the past 16 years as a bridge to cardiac transplantation in patients with end-stage congestive heart failure. The Stanford experience represents 53 patients (48 male, 5 female) with a mean age of 44 +/- 13 years (16 to 62) and a mean support time of 56 +/- 76 days (1 to 374). Complications with LVAS use consisted predominantly of bleeding (43%), infection, (30%), and embolic cerebrovascular events (24.5%). Sixty-six percent of the supported patients were successfully bridged to cardiac transplantation. In animal studies, 4 sheep had the totally implantable configuration in place for a cumulative duration of 1 year with 1 animal supported for 260 days. The next generation Novacor LVAS will be small, quiet, and fully implantable without the need for volume compensation. It will also provide physiologic pulsatile flow and will be fail-safe.

Background . Two modifications of the surgical implantation protocol for the Penn State Total Artificial Heart (ETAH) were evaluated: Phrenic nerve ischemia was prevented by minimizing dissection and traction; and hemostasis was augmented and ETAH cuff anastomoses reinforced by using fibrin glue. Methods . Thirteen Holstein calves underwent orthotopic surgical implantation of the Penn State ETAH between February 1998 and August 2000. Mean hemodynamic and laboratory chemistry variables from the first postoperative week were compared between calves receiving the original (n = 7) and modified (n = 6) protocol. Results . Calves assigned to the modified protocol displayed an improvement in the Po 2 /Fio 2 ratio compared to original (419.4 ± 17.5 vs 336.3 ± 35.4, respectively; p = 0.05). All additional parameters were equivalent between groups. The percent survival of animals receiving the modified protocol at 2, 4, and 12 weeks was higher than that of animals that underwent the original protocol. Original-protocol calf deaths consisting of hemothorax (n = 3), and respiratory failure (n = 1) were prevented in the modified protocol. Conclusions . Our results suggest that manipulations in surgical protocol may promote increased survival in calves implanted with the Penn State ETAH.

Background . Recent scientific and clinical data suggest that chronic mechanical ventricular unloading may lead to myocardial recovery. Evaluating and monitoring patients for myocardial recovery and the optimal methods of weaning the left ventricular assist device are not well defined. Methods . Six patients with advanced heart failure and severe mitral regurgitation have undergone successful bridge to recovery using a Thoratec left ventricular assist device. Data that details their monitoring for myocardial recovery and weaning from the left ventricular assist device were prospectively collected. Results . Clinical data collected during the recovery phase included chest roentgenogram, echocardiography, plasma norepinephrine, tumor necrosis factor-α, bioimpedance, and cardiopulmonary exercise testing (peak oxygen consumption). Normalization of these variables with a 10% increase in the peak oxygen consumption was obtained before weaning. The Thoratec device rate and percent systole were manipulated to allow gradual reloading of the ventricle. The weaning process occurred for more than 5 to 10 days to allow time for observation of the ventricle and its response to the increasing workload. Conclusions . Select patients with advanced congestive heart failure and severe mitral insufficiency can benefit from mechanical device support. We describe our technique of monitoring for myocardial recovery using clinical variables. Our technique of weaning allows for gradual reloading of the ventricle and a longer period of observation before device removal. Additional research is needed to determine which variables will accurately predict long-term myocardial recovery and the optimal weaning method.